1. Perioperative Risk Assessment
Matt Brugger MD
Rush University Hospitalists
Division of Hospital Medicine
Director of Clinical Operations
Rush University Medical Center
October 2, 2015

2. No disclosures or conflicts related to this presentation.
Focused on the Perioperative risk evaluation for patients undergoing Non-Cardiac surgery.

3. Objectives
Evaluate a patient’s perioperative risk assessment using the patient’s risk factors, surgical risks, and functional status.
Show several different risk assessment tools.
Demonstrate use of revised cardiac risk index in specific cases.
Provide updates from the 2014 guidelines and updated risk algorithm.

4. Example: Case 1
44 year old female with history of CAD, diabetes on insulin, stroke who presented with dysfunctional uterine bleeding.
Asked to provide pre op risk evaluation for exam under anesthesia, possible hysterectomy.
Functional status adequate
Surgery intermediate to high risk (pending if abdominal hysterectomy consider high risk)
Low or elevated risk?
Elevated
Further testing warranted?
Stress testing
Stress deferred as further information received on review of OSH records (has 3 vessel CAD), bypass recommended 2 years prior.
Patient refused further evaluation by CV Surgery, stated she would not have bypass. Uneventful hysterectomy performed.

5. Many patients going for non cardiac surgery are at risk for perioperative cardiac event.
Major adverse cardiac events (MACE) may include non fatal myocardial infarction, non fatal cardiac arrest, cardiac death, pulmonary edema, ventricular fibrillation, complete heart block, need for revascularization.
Most recent guidelines from ACC/AHA were released in August 2014, previous update was in 2007.

6. Perioperative risk evaluation prior to surgery is commonly asked of cardiologists, internists, and anesthesiologists.
It is not a cardiac clearance, but a risk evaluation/assessment.
It can be a complex decision, that takes cardiac and non cardiac factors into account.
Perioperative cardiac evaluation is not the only aspect that can be addressed by these evaluations.

7. Example: Case 2
73 year old female with past medical history of RA, COPD, HTN, DM2, neuropathy who presented with shoulder RA and arthropathy for right reverse total shoulder arthroplasty.
DM type 2 (not on insulin)
Intermediate risk surgery
No SOB/CP
Adequate functional status
Elective surgery
Any further testing?

8. Perioperative Course No further testing done, proceeded to OR.
T inversions in OR
EKG with mild inversions, slight ST depression
Repeat EKG similar, but persistent mild ST depressions
TTE normal.
Stress markedly abnormal
Found to have severe 3 vessel CAD on coronary angiogram
CABG scheduled (within 2 weeks)
Developed new crushing left sided chest pain with subsequent cardiogenic shock, required emergent CABG
Was low risk on evaluation by revised cardiac risk index (would have been by other risk evaluations as well), but illustrates why it is not a clearance, but a risk evaluation.

9. Perioperative Risk Evaluation
Several factors go into the determination of the perioperative risk evaluation.
Patient specific risk factors
Surgery risk factors
Functional status
Urgency of the surgery
Determination if patient is having ACS
Need for further testing
Other perioperative considerations

10. Patient Risk Factors Main predictors Other predictors History of CAD
History of CHF
History of TIA/Stroke
History of Diabetes on insulin
History of CKD with Cr over 2.
Emergent surgery
PAD (CAD equivalent?)
Other predictors
Atrial fibrillation/arrhythmia with uncontrolled ventricular rate
Obesity
Pulmonary hypertension
Aortic stenosis
Recent PE
Diabetes (not on insulin)
Others (multiple)

11. Cardiac Risk Stratification for Noncardiac Surgical Procedures
High risk (reported risk of cardiac death or nonfatal myocardial infarction [MI] often greater than 5%)
Aortic and other major vascular surgery
Peripheral artery surgery
Intermediate risk (reported risk of cardiac death or nonfatal MI generally 1 to 5%)
Carotid endarterectomy
Head and neck surgery
Intraperitoneal and intrathoracic surgery
Orthopedic surgery
Prostate surgery
Low risk (reported risk of cardiac death or nonfatal MI generally less than 1%)
Ambulatory surgery
Endoscopic procedures
Superficial procedures
Cataract surgery
Breast surgery
Fleisher, LA. et al. Journal of American College of Cardiology 2007; 50:159.

12. Functional Status
Functional status can be expressed in metabolic equivalents (1 MET is defined as 3.5 mL O2 uptake/kg per min, which is the resting oxygen uptake in a sitting position).
Can take care of self, such as eat, dress, or use the toilet (1 MET)
Can walk up a flight of steps or a hill or walk on level ground at 3 to 4 mph (4 METs)
Can do heavy work around the house such as scrubbing floors or lifting or moving heavy furniture or climb two flights of stairs (between 4 and 10 METs).
Can participate in strenuous sports such as swimming, singles tennis, football, basketball, and skiing (>10 METs)
Cohn, SL, Fleisher, LA. UpToDate 2014.

13. Duke Activity Status Index (DASI)
Hltaky MA Boineau RE et al. Am J Cardio. 1989; 64:

14. Duke Activity Status Index (DASI)
Duke activity status index = Sum (values for Yes for 12 questions)
Estimated peak oxygen uptake (VO2 peak) in mL/kg/min = (0.43 X (Duke Activity Status Index)) + 9.6
METS = VO2 peak / 3.5 mL/kg/min
Somewhat cumbersome to ask all these questions.
Looked at an easier way, a sum of 10.2 or higher is 4 METS or higher.
If yes for questions1-4 (or yes to question 10 in place of 4), they have 4 or greater METS.

15. Example: Case 3
50 year old male with significant past medical history of emphysema, tobacco abuse who presents with worsening right arm/leg pain and weakness.
Surgery is time sensitive intermediate risk surgery.
At risk for worsening neurologic deficits and paralysis if not done.
Functional status is limited due to his weakness, but was not having SOB/CP prior to this with exertion, and as recently as 2 months ago could exert himself to 4 or more METS.
Pre op risk evaluation - revised risk score likely 0, possibly 1 if considered that could have had a stroke (listed in history, but symptoms more explained by cervical stenosis).
Either way risk is % of major adverse cardiac event, and is low cardiac risk for surgery.
No further cardiac workup recommended prior to surgery.

16. Common Risk Calculators Used
Revised Cardiac Risk Index (RCRI)
American College of Surgeons National Surgical Quality Improvement Program Risk Calculator (ACS-NSQIP)
Gupta Myocardial Infarction/Cardiac Arrest Risk Calculator (MICA)

17. Revised Cardiac Risk Index (RCRI)
Revised Goldman cardiac risk index (RCRI)
Six independent predictors of major cardiac complications
High-risk type of surgery (examples include vascular surgery and any open intraperitoneal or intrathoracic procedures)
History of ischemic heart disease (history of MI or a positive exercise test, current complaint of chest pain considered to be secondary to myocardial ischemia, use of nitrate therapy, or ECG with pathological Q waves; do not count prior coronary revascularization procedure unless one of the other criteria for ischemic heart disease is present)
History of HF
History of cerebrovascular disease
Diabetes mellitus requiring treatment with insulin
Preoperative serum creatinine >2.0 mg/dL (177 µmol/L)
Rate of cardiac death, nonfatal myocardial infarction, and nonfatal cardiac arrest according to the number of predictors
No risk factors percent (95% CI: )
One risk factor percent (95% CI: )
Two risk factors percent (95% CI: )
Three or more risk factors percent (95% CI: )
Lee TH, Marcantonio ER, Mangione CM, et al. Circulation 1999; 100: Devereaux PJ, Goldman L, Cook DJ, et al. CMAJ 2005; 173:627.

18. Lee Revised Cardiac Risk Index
1. High-risk surgical procedures
Intraperitoneal
Intrathoracic
Suprainguinal vascular
2. History of ischemic heart disease
History of myocardial infarction
History of positive exercise test
Current complain of chest pain considered secondary to myocardial ischemia
Use of nitrate therapy
ECG with pathological Q waves
3. History of congestive heart failure
History of congestive heart failure
Pulmonary edema
Paroxysmal nocturnal dyspnea
Bilateral rales or S3 gallop
Chest radiograph showing pulmonary vascular redistribution
4. History of cerebrovascular disease
History of transient ischemic attack or stroke
5. Preoperative treatment with insulin
6. Preoperative serum creatinine > 2.0 mg/dL
Lee TH, Marcantonio ER, Mangione CM, et al. Circulation 1999; 100:1043.

19. Lee Revised Cardiac Risk Index
RISK OF MAJOR CARDIAC EVENT
Points Class Risk
0 I 0.4%
1 II 0.9%
2 III 6.6%
3 or more IV 11%
Similar to rates of the Goldman Revised Risk Index, slightly higher risk than Goldman Revised Risk Index for those with 2 or more points.
Lee TH, Marcantonio ER, Mangione CM, et al. Circulation 1999; 100:1043.

20. Surgery Risk Calculator (ACS-NSQIP)
Consists of 20 patient factors plus the surgical procedure.
More comprehensive than other risk calculators.
Much more involved, not as quick to do at the bedside.
Not externally validated (as compared to RCRI)

21. © 2007 - 2015, American College of Surgeons National Surgical Quality Improvement Program.

22. Gupta Risk Calculator (MICA)
Evaluates risk of Perioperative Myocardial Infarction or Cardiac Arrest (MICA) using several variables.
Age
American Society of Anesthesiology (ASA) Class
Preoperative Creatinine
Preoperative Functional Status
Procedure

23. American Society of Anesthesiology Classification
ASA Classification:
1. A normal healthy patient.
2. A patient with mild systemic disease
3. A patient with severe systemic disease
4. A patient with severe systemic disease that is a constant threat to life.
5. A moribund patient who is not expected to survive without the operation.
6. A declared brain dead patient whose organs are being removed for donor purposes.

24. Example: Case 4
61 year old female with significant past medical history of 80 pack year smoking history who presents with a lung mass and a L frontal brain lesion (CT with edema, minimal midline shift).
Pre op risk evaluation No personal history of CAD, MI, DM, CKD, stroke, CHF, arrhythmia, DVT. No symptoms of OSA. Mother with MI at 70. No cancer history.
Able to walk more than 4 blocks, more than 2 flights of stairs without issues. No limitations due to SOB/CP. No current SOB/CP.
Low cardiac risk (revised risk score 0), with risk about 0.4% for major adverse cardiac events.
Good functional status (over 4 METS), can do 4+ blocks, 2 or more flights of stairs.
Surgery likely intermediate risk. Time sensitive surgery.
EKG without ischemia. No cardiac history of symptoms.
No further cardiac workup recommended at this time

25. 2007 ACC/AHA Guidelines
Fleisher, LA. et al. Circulation 2007; 116:

26. Example: Case 5
75 year old male with history of CHF, Diabetes (on insulin) ESRD who presents for right hip arthroplasty. Due to pain, really cannot ambulate nor do stairs (METS under 4).
Surgery intermediate risk. Elective.
Functional status poor by history (difficult to determine due to functional limitations)
Elevated cardiac risk (revised risk score 3) with risk of MACE of 11%.
EKG with non specific T wave changes (stable from previous)
Should we do further testing?
If so, what testing would you like?

27. Example: Case 6
75 year old male with history of CHF, Diabetes (on insulin) ESRD who presents with acute traumatic right hip fracture while ambulating to commode. Due to pain, really cannot ambulate nor do stairs at baseline (METS under 4).
Surgery intermediate risk. Urgent surgery
Functional status poor by history (difficult to determine due to functional limitations)
Elevated cardiac risk (revised risk score 3) with risk of MACE of 11%.
EKG with non specific T wave changes (stable from previous)
Should we do further testing?
If so, what testing would you like?

28. 2014 Updates to 2007 ACC/AHA Guidelines
Algorithm for assessing cardiac risk
Definitions of urgency and risk
Emergency procedure:
Need for OR in < 6 hours
Urgent procedure:
OR in 6-24 hours
Time-sensitive procedure:
Delay of > 1-6 weeks (for workup) will negatively affect outcome
Elective procedure:
Can be delayed up to 1 year
Determination if patient is having Acute Coronary Syndrome (ACS)
Simplification of risk into low risk or elevated risk.

29. 2014 Perioperative Guideline
Fleisher, LA. et al. Journal of the American College of Cardiology 2014;64(22):e77.

30. Stepwise Approach Emergent surgery Urgent/Elective surgery
Proceed to surgery
Perioperative risk factor treatment/optimization especially post op.
Urgent/Elective surgery
Is patient having ACS
If yes, Cardiology evaluation
Estimate risk of major adverse cardiac events (MACE)
Definitions changed from low, intermediate and high risk to low and elevated. Most intermediate risk patients were being treated the same as high risk.

31. Stepwise Approach Low risk Elevated risk Proceed to surgery
Evaluate functional status
Functional status moderate to excellent (at least 4 METS)
Functional status poor or unknown
Determine if testing will affect management
If testing will change management, then stress testing is reasonable
Further testing usually means stress test, but occasionally could also mean echocardiogram.

32. Example: Case 7
74 year old male with past medical history of HTN, DM (on insulin), HLD, Prostate cancer, seizures, Left ischemic CVA (right hemiparesis) who presented with acute on chronic SDH. Was on ASA/Plavix, had a fall. Now with worsening lethargy.
Subfalcine herniation, right sided lesion has enlarged and is exerting significant mass effect
Surgery is urgent/emergent (to be done that day per surgeon)
Revised risk score 2 or 3 (3 if emergent surgery), elevated cardiac risk.
Functional status poor (right hemiparesis)
EKG without ischemia/previous infarction
Other testing indicated?
If so, what testing?

33. Example: Case 8
76 year old female with lung cancer, DM type 2 (on insulin) HTN, portal vein thrombus, admitted with lethargy, dizziness from ICH, possible hemorrhagic metastasis. Symptoms improving on dexamethasone.
Patient low cardiac risk for surgery with Revised risk score 1 (DM on insulin), corresponding to a risk of major adverse cardiac events of 0.9%.
Surgery intermediate risk, and time sensitive given neurologic changes related to bleeding (which are a bit better on steroids).
Functional status over 4 METS.
EKG sinus bradycardia without ischemia. Possible infarction noted on previous EKG's. Stress test done 2 months ago without ischemia.
No further cardiac workup recommended prior to surgery.

34. 2014 Perioperative Guideline
Fleisher, LA. et al. Journal of the American College of Cardiology 2014;64(22):e77.

35. Perioperative EKG Not all patients going for surgery need an EKG.
Commonly done on just about all patients.
No standard age or risk factor cutoff to determine when it is needed.
Ideal timeframe prior to surgery when checked is not known.
General consensus is somewhere within 3 months prior to surgery.
Minimal benefit in asymptomatic patients going for low risk surgery.
Reasonable to check in patients with known CAD, PAD, arrhythmia, strokes, structural heart disease or going for elevated risk surgery.

36. Perioperative Echocardiogram (TTE)
Minimal benefit for routine evaluation of left heart function/Ejection fraction (EF).
Reasonable to check when:
Moderate to severe stenosis or regurgitation suspected with no recent (likely 1 year) or a new change in clinical status or physical since last evaluation.
Dyspnea of unknown origin.
Patient with CHF with a change in clinical status or worsening dyspnea.
Consider if known left heart dysfunction and last evaluation over a year.

37. Example: Case 9
73 year old female with significant past medical history of DM type 2 not on insulin), HTN, GERD, OA, renal cell cancer, breast cancer who presents with worsening LE pain, weakness and back pain.
Revised risk score 0. Risk of MACE about 0.4%
Surgery (tumor metastases resection) intermediate risk.
Probably time sensitive (possibly elective) as pain and weakness worsening and progressive, but no cord compression nor acute fracture.
Stress 2/2014 which was normal, and showed normal LV function at that time.
The main current abnormality is unexplained DOE, present for 1-2 years.
Reports of orthopnea, but she has no signs of CHF on her exam with clear lungs, no LE edema, no JVD.
No murmur nor symptoms to suggest aortic stenosis.
Further testing?
What test would you like if any?

38. Other Perioperative Considerations
OSA
Suspected OSA can be evaluated by the STOP BANG score.
If known, continue patients CPAP.
Elevate head of bed for patient when sleeping if not on CPAP.

39. OSA Risk, STOP BANG Score
Height ___________ Weight _________ Age __________ Male / Female ___________
STOP-BANG Sleep Apnea Questionnaire
STOP
Do you SNORE loudly (louder than talking or loud enough to be
heard through closed doors)? Yes No
Do you often feel TIRED, fatigued, or sleepy during daytime? Yes No
Has anyone OBSERVED you stop breathing during your sleep? Yes No
Do you have or are you being treated for high blood PRESSURE? Yes No
BANG
BMI more than 35kg/m2? Yes No
AGE over 50 years old? Yes No
NECK circumference > 16 inches (40cm)? Yes No
GENDER: Male? Yes No
TOTAL SCORE
High risk of OSA: Yes 5 – 8
Intermediate risk of OSA: Yes
Low risk of OSA: Yes

40. Example: Case 10
75 year old male with significant past medical history of OSA, PE, HTN, hypothyroidism, HLD who presents with acute onset of weakness over the past week with inability to ambulate well due to recurrent falls. No history of MI, CAD, CHF, arrhythmia, CKD, DM type 2, stroke. Able to do 4 blocks and 2 flights of stairs prior to this event.
Patient low risk for intermediate risk surgery by revised risk index. RCRI score 0, corresponding to 0.4% risk of major adverse cardiac events.
Surgery (severe spinal stenosis), intermediate risk. Time sensitive if causing his symptoms.
Functional status over 4 METS (until weakness in past few days), no active cardiac complaints. No SOB/CP.
EKG essentially normal, unchanged from previous (from 3 months ago when had previous surgery).
no further cardiac testing recommended prior to surgery
continue CPAP post op

41. Other perioperative considerations
Pulmonary hypertension
Can be associated with higher complication rate.
Evaluation of RV function prior to surgery reasonable.
Evaluation by pulmonary HTN specialist recommended if any significant RV dysfunction or high pulmonary artery pressures.
Chronic steroid use or adrenal insufficiency
Stress dosing of steroids recommended
Hypothalamic pituitary access can be affected by steroids even taken just a week, and time of affect is unpredictable. (days to months)
For any chronic use of 20 mg prednisone (or equivalent) for 3 or more weeks.
Not needed for doses of prednisone 5 mg or lower daily.
No consensus for doses in between 5-20 mg, but typically will receive stress dosing for doses over 5 mg prednisone daily.

42. Other perioperative considerations
Anticoagulation
A challenging topic
Main question is if therapy interrupted for surgery, is bridging necessary?
Liver disease
In patients with cirrhosis, risk of perioperative morbidity and mortality much higher than risks calculated based on cardiovascular risk.
If evaluating patient with cirrhosis, recommend having hepatology involved given the risks.
Most elective surgeries are not recommended in setting of decompensated cirrhosis.

43. Other Perioperative Considerations
Conduction abnormalities
Generally without advanced heart block, most do not progress to complete heart block perioperatively.
Can be concerning in some cases
Case 11
85 year old male with history of DM type 2, stroke, CAD with MI, CABG, CKD, HTN, gout who presents with HA. Found to have cerebellar lesion
Patient with 1 degree AV block, 2nd degree type 1, RBBB, and LAFB (Trifasicular block).
Bradycardia (into 20’s) and dropped beats,
During stress had accelerated idioventricular rhythm.
Appeared to have a few 8-10 beat runs of V tach on monitor.
EP evaluation (patient received transvenous pacer prior to surgery)

44. Questions?

45. References
Bilimoria KY, Liu Y, Paruch JL. et al. J Am Coll Surg Nov;217(5):
Chung, F. Yegneswaran, B. et al. Anesthesiology 2008; 108:
Cohn, SL, Fleisher, LA. UpToDate Accessed September 2015.
Devereaux PJ, Goldman L, Cook DJ, et al. CMAJ 2005; 173:627.
Fleisher, LA. et al. Circulation 2007; 116:
Fleisher, LA. et al. Journal of American College of Cardiology 2007; 50:159.
Fleisher, LA. et al. Journal of American College of Cardiology 2014;64(22):77.
Gupta, P. et al. Circulation 2011;124(4):
Hltaky MA Boineau RE et al. Am J Cardio. 1989; 64:
Lee TH, Marcantonio ER, Mangione CM, et al. Circulation 1999; 100:1043.
Shaw, M. Cleveland Clinic Journal of Medicine 2002; 69 (1): 9-11.